Process for the extraction of precious metals from solutions thereof
US4390366A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 1, 1981 |
| Grant date | Jun 28, 1983 |
| Priority date | — |
| Expiry date | Sep 1, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A process for sequentially and selectively separating gold and platinum group metals from aqueous solutions containing them is disclosed. First, ruthenium and osmium are oxidized to their tetroxides and then removed from the solution. Then, gold is removed by solvent extraction preferably with dibutyl carbitol. Next, palladium and platinum are removed by solvent extraction with an alkyl sulphide and tributyl phosphate respectively, care being taken to reduce iridium in solution before platinum extraction to prevent it extracting with the platinum. Then the iridium is reoxidized and removed from solution. Finally, rhodium is removed from the solution. Using this process gold, platinum and palladium of saleable purity can be extracted directly without the need for further refining steps.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.